Effects of varying temperature on the performance of reinforced concrete

Abstract

To obtain a more robust understanding of the effects of temperature on crack widths, stiffness, strength and short term creep behaviour of reinforced concrete elements to improve structural assessment techniques. Crack widths are monitored in four small scale reinforced concrete tension specimens, while exposed to temperature cycles. Four large scale beams, two at room temperature and two at −20 °C, are loaded under four point bending for 48 h at service load before being tested to failure. Crack width behaviour and mid-span deflections are monitored. A comparison of the room temperature and low temperature test results show that the crack widths tend to decrease at lower temperatures in members that are free to expand and contract. The beams also saw an increase in strength that was dependent on the failure mode, but saw no noticeable increase in stiffness. Lastly, short-term creep behaviour was reduced in the low temperature beams. The observed cracking behaviour and beam test results indicate the potential for an increase in shear capacity for beams at lower temperatures.